by Peter Wilson, Special for USA TODAY

by Peter Wilson, Special for USA TODAY

CARACAS, Venezuela - Venezuela´s National Assembly will hold its first session of the year Saturday amid growing uncertainty about whether cancer-stricken Hugo Chávez will be able to be sworn in for a fourth term on Thursday, as required by the constitution.

Opposition legislators are expected to push for a detailed medical report about Chávez, 58, who underwent his fourth surgery in Cuba for cancer on Dec. 11. He hasn't been seen since, amid growing rumors that he is seriously ill or dying.

The National Assembly will either agree to delay Chávez´s inauguration or approve the Supreme Court going to Cuba to swear him in, said Risa Grais-Targow, an analyst with the Eurasia Group.

Information Minister Ernesto Villegas said Thursday night that Chávez is being treated for "respiratory deficiency" after complications from a severe lung infection. It was the first time the government has described the lung infection as "severe."

Under the constitution, Chávez must be sworn in by Jan. 10 before the assembly or, failing that, before the Supreme Court at another location. If Chávez is unable to be sworn in, the constitution states that Assembly President Diosdado Cabello would have 30 days in which to call for new elections.

Chávez was re-elected in October to a fourth term with about 55% of the vote. That term would end in 2019.

The parliamentary session coincides with growing pressure on Vice President Nicolas Maduro to reveal more information about Chávez and his condition. Chávez has never said what kind of cancer he is fighting nor what the long-term prognosis is. He first underwent an operation for cancer in mid-2011 and has undergone chemotherapy and radiation treatment.

Maduro accused the opposition of spreading rumors about Chávez and his illness in a bid to destabilize the country. Maduro said that the government has been very forthcoming about Chavez´s condition, releasing 26 bulletins in 22 days.

Grais-Targow agreed that the government has become more forthcoming, "but we're still missing a lot of details."

Chávez, a fiery populist who has often attacked the U.S. and capitalism as part of his socialist revolution, has been president since 1999. He survived a coup attempt in 2002, and a recall vote in 2004.